Allergy Medications for Dogs

The misery of allergies isn’t exclusive to humans. Dogs suffer from allergies, too! They get seasonal, contact, and food allergies just like humans do. Whether your dog is suffering from intense sneezing or itchy skin, there are pharmaceutical solutions to help manage a variety of allergy types.

Antihistamines for Dogs

Antihistamines are the most frequently used allergy medications. An allergic reaction is in response to inflammation caused by the production of histamine. If histamine isn’t produced, then the allergic reaction doesn’t occur. How much histamine is produced is directly related to how much the dog reacts to the allergen. Some dogs will develop minor reactions to bee stings, for example, while other dogs can go into anaphylactic shock if they get a vaccine their body can’t process. Antihistamine medications block histamine from being produced or greatly reduces how much is made. Every system reacts differently to antihistamines, so finding one that will work is going to be a process of elimination. Since this type of medication is only effective in about 30 percent of canine patients, it should be part of a series of therapies instead of being used on its own.
Diphenhydramine (Benadryl) is the most well-known antihistamine on the market. It’s administered to treat itching produced by an allergic reaction, especially in situations where a dog develops hives. Dogs brought into a vet clinic with an acute allergic reaction (facial swelling, hives, difficulty breathing) are given an injection of diphenhydramine. If that is effective, the vet recommends a daily regimen of the drug for the next 48 to 72 hours. For long-term use, it’s particularly effective in helping dogs with atopic allergies when they come into contact with an allergen. Diphenhydramine has a sedative effect on dogs, so don’t be surprised if your dog becomes quite drowsy and quiet with each dose.
Hydroxyzine is prescribed for long-term use in dogs with an atopy allergy. It works very well in dogs with seasonal allergies who can’t avoid their triggers. It’s also used to treat dogs who have been bitten by snakes, are experiencing vaccine reactions, and allergic reactions to bee/insect bites. Side effects are similar to that of diphenhydramine, like drowsiness and an increased thirst due to a dry mouth.
The drug, loratadine (Claritin), is safe for dogs if it’s used under the supervision of a veterinarian. It’s given to dogs for itchy skin due to allergies, as well as reducing vaccine side effects or to reduce the inflammation from mast cell tumors. It isn’t used to treat sneezing or any nasal/ocular discharge resulting from allergies like it is in humans. If your vet has said it’s okay to use on your dog, make sure you read the label. Claritin-D contains psuedoephedrine, a decongestant that’s toxic to dogs, and should never be administered.

Giving Dogs Steroids

Steroids are used for both long- and short-term allergy treatment. Dogs with severe chronic allergies may require long-term use of steroids while acute allergic reactions only need a short course. Steroids are most effective when treating severe itching or inflammation. Despite their efficacy, your vet won’t immediately give your dog steroids for a chronic condition unless other treatments haven’t worked.
Steroids should only be used under the close supervision of your vet. Steroids are a potent drug and shouldn’t be used at the drop of a hat. Corticosteroids have a variety of side effects, including a sharply increased appetite, increased thirst/urination, depression or hyperactivity, panting, and diarrhea. Side effects appearing during short courses of corticosteroid therapy will go away once the dog is done taking the drug, but long-term use risks permanent damage. Higher doses suppress the immune system, increasing the risk of a variety of infections. Other dogs experience dry, itchy skin. More seriously, steroids can cause diabetes, adrenal suppression, and liver damage. This is why vets are conservative in their use of steroids.

Immunosuppressive Drugs for Dogs

Cyclosporine (Atopica) is used in organ transplant patients because it suppresses the immune system to prevent the body from rejecting its new organ. In the past few decades, it’s become popular in treating inflammatory skin disorders in dogs. It’s prescribed to treat dry eye, inflammatory bowel disease, a dangerous blood disorder called immune-mediated hemolytic anemia, and atopic dermatitis If your vet puts your dog on cyclosporine, it’s because other therapies haven’t worked and cyclosporine has an 80 percent success rate. It’s a lifetime drug, meaning your dog will be on it for the rest of their life. Your dog will go on a daily dose for four to six weeks, then the dose and frequency will be decreased until the lowest effective dose possible is found.
Cyclosporine use necessitates the need for frequent physical exams and twice-yearly bloodwork and urinalyses to ensure the organs are functioning properly.

Applying Topical Therapies On Dogs

Sometimes it takes more than oral medication to ease the discomfort of allergies. Topical medications are often used in conjunction with oral therapies. Topical treatments include medicated shampoos, topical anesthetics, and steroid creams.
Medicated shampoos are recommended because allergy-prone dogs benefit greatly from frequent bathing. The anti-itch medications in the shampoos help, but frequent baths also reduce how many allergens are on the skin and in the coat. Human shampoos/soaps should never be used on your dog because they dry their skin out and exacerbate their symptoms.
Topical steroids should only be used when recommended by your vet. Even though they’re only applied to the skin, excessive application increases the risk of skin infections or the skin can become excessively thin.

Fatty Acids and Dogs

Diet changes are beneficial with or without the use of medications. Research shows that omega-3 fatty acids are beneficial in treating skin conditions caused by allergies. They don’t work in every dog, but if the fatty acids do work, many dogs improve vastly. It can take a few weeks to months to see any improvement, so it isn’t a quick cure. Your vet might recommend using fatty acids and antihistamines together before suggesting steroid use. Use omega-3 acids derived from fish oil; omega-6 fatty acids make allergies worse.

Biotin for Dogs

Biotin is a B vitamin that aids in the health of skin and hair. Studies show dogs find relief from dry skin or seborrhea when their diet is supplemented with biotin. When used in conjunction with omega-3 fatty acids, it helps relieve dry, itchy skin. Biotin supplements for dogs are available, but it’s found naturally in brewer’s yeast.
Allergies may come and go or they can be a lifelong battle for you and your dog. Figuring out your dog’s triggers may take allergy testing and a lot of medication trials, but knowing the root of your dog’s misery goes a long way in giving them a comfortable life and alleviating their symptoms.

SmartDogOwners.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.
*Amazon and the Amazon logo are trademarks of Amazon.com, Inc., or its affiliates.
Additionally, SmartDogOwners.com participates in various other affiliate programs, and we sometimes get a commission through purchases made through our links.